Cash register burglar alarm



March 1942- F. c. w. STELTER ETAL 2,276,632

CASH REGISTER BURGLAR ALARM Filed May 15, 1939 r- 9 I I I I 11 I p. I I I 4 I I 9 2 5 5 i r I I fllllllnwlllllllllllll/l maw m may Patented Mar. 17, 1942 UNITED CASH REGISTER BURGLAR ALARM Francis 0. W. Stelter and Anna Dorothy M. Stelter, New York, N. Y.

Application May 15, 1939, Serial No. 273,780

9 Claims.

This invention relates to alarm systems and apparatus and more particularly to protective equipment for cash registers, cash drawers and the like, which are operated by release buttons or keys.

, It is a general object of the present invention to provide a novel and improved alarm system.

More particularly it is an object of the invention to provide, in combination with a cash register having a sliding drawer and operating keys, an alarm circuit and switching arrangement associated with the drawer and keys whereby any opening of the drawer without the pressing of a selected one of the keys causes the operation of a suitable alarm.

An important feature of the invention resides in the use of one of the conventional keys on the cash register which must be operated in combination with any others desired to open the cash drawer without giving the alarm.

Another important feature of the invention resides in the arrangement of the switch mechanism whereby a normally closed-circuit switch is opened by the selected key while a normally open-circuit switch is closed by the opening of the drawer, the two switches being arranged in series with an alarm circuit.

Still another important feature of the invention consists in the mechanical cooperation of the two switches whereby the normally closedcircuit one is opened, by the operation of the proper key, prior to the closing of the normally opened-circuit one to prevent any instantaneous operation of the alarm when the cash drawer is properly operated.

Other and further features and objects of the invention will be more apparent to those skilled in the art upon a consideration of the accompanylng drawing and following specification wherein is disclosed a single exemplary embodimerit of the invention with the understanding that such changes may be made therein as fall within the scope of the appended claims without departing from the spirit of the invention.

In said drawing:

Figure 1 is a side elevation of a conventional cash register, a portion of the housing being broken away to expose a switch mechanism;

Figure 2 is a fore and aft vertical section through the housing of the switch structure exposing the contact elements; and

Figure 3 is a schematic circuit arrangement of the switches, alarm and current source.

A recent wave of small store hold-ups has made it highly desirable to provide some suitable and simple means for sounding an alarm, preferably in an adjacent store, nearby police station, protective agency or the like, while at the same time complying with the command of the burglar, to prevent physical violence. The average small store is equipped with a more or less conventional cash register or cash drawer in which the drawer is slidably mounted to be automatically opened by a spring or like mechanism when released by the operation of one or more keys.

Ordinarily such keys are marked to designate the amount of a sale, the type of transaction and the salesman operating the same. Thus in most circumstances a plurality of keys are pressed to release the drawer. It is the purpose of the present invention to provide an alarm mechanism which can be actuated by failure to press one key of a group without making the action apparent to those unacquainted with the alarm arrangement of the cash register. Thus, on command, the clerk may open the drawer of the register by an apparently normal action and yet give an alarm without it being known to the robber. If the cash drawer is opened by the burglar by following the usual procedure, the particularly selected key which prevents the giving of an alarm will not be actuated and the alarm will be given.

Broadly, the invention includes an alarm circuit and a suitable signal appropriately located and connected to a switch mechanism completely hidden within the cash register, preferably behind the drawer, which mechanism includes a normally closed-circuit switch and a normally open-circuit switch in series with the alarm circuit. The first switch is arranged to be opened upon pressing the selected key while the second switch is arranged to be closed upon any opening of the drawer whereby the alarm will be given every time the drawer is opened unless prevented by pressing the selected key.

Referring now to the drawing, there is shown at E0 the casing of any conventonal cash register, which is provided with a plurality of keys or buttons I I, which may include both those for registering the amount of a sale and those for indicating the salesman, type of transaction, or

and spring opened under a suitable bias for access to the cash contained therein.

The switch mechanism of the present invention may conveniently be arranged in a single housing M of such size that it can be accommodated at the rear of the drawer and be completely hidden within the cash register. The housing may have a suitable flange !5 permitting it to be secured down to the base [6 of the cash register casing. Within the housing are two switches C and O, the first being normally closed by having its movable contact roller 18 engaged with the spaced contact springs in. The roller is carried on a vertically slidable bar 2% guided by having the pins 2| and 22 which are secured thereon operating in vertical slots 23 and er respectively in the side walls of the housing M. A spring pressed ball 25 engages respectively with notches 26 and 21 in the edge of the bar 26 to hold the bar with the roller positioned in closed or open position.

In a like manner switch 0 includes a contact roller so carried on a bar 3! guided for horizontal movement by the pins 32 and operating respectively in slots 3 and 35 in the side walls of the housing. This roller is normally maintained out of contact with the springs 35 while the cash drawer i3 is closed, by mechanism which will now be described.

Preferably mounted on the outside of the housing of the switch is a bell crank lever 36, pivoted at 4!, and having the lower arm 4-2, curved forwardly as at 43 for cooperation with the rear face of the drawer 53 or with a suitable protuberance thereon. The lower end of this arm is enlarged and provided with a vertical slot 4 engageable over an extension of the pin 33, whereby, when the drawer is in a closed position, this pin is held rearwardly and the lower switch '0 maintained open. A compressed helical spring 46 bearing between an abutment 41 on the switch housing and the rear of the enlarged end of the arm 42 insures positive closing of the switch 0 as soon as the drawer moves forwardly a short distance.

A second and substantially horizontal arm 58 on the bell crank mounts a light helical spring 49, the upper end of which bears beneath the lower end of an arm 59 rigidly mounted on an extension of the pin 2:2 and this arm has a pin and slot connection 5! with the lever {i2 forming part of the registering and drawer operating mechanism of the cash register which is associated with the selected key it.

The spring 69 is of sufficient strength, when raised to its upper position by the bell crank, to position the switch C with the ball 25 in the notch closing the circuit. Thus the normal position of the two switches, when the drawer I3 is closed, is shown in Figure 2 or in Figure 3 and since they are connected in series by the wire 54 to each other and by wires 55, 56 and dl'to the alarm and source of current 59, it will be seen that the circuit is open and the alarm inoperative. Should the drawer now be opened by pressing others than the selected key 12, pressure is released from the arm 42 and the bar 3| moves to the left as viewed in Figure 2 under the urge of spring it, carrying the contact 33 between the contact springs 36 and completely closing the alarm circuit. Since the other switch C is already closed, the alarm is operated.

When the proper person desires to open the cash register, without giving the alarm, he includes among the keys pressed that numbered l2 so that the downward movement of its lever 52 causes the pin and slot arrangement 5| to push down on the arm 59, compressing the light spring 49, opening the switch C and permitting the notch 21 to be engaged by the ball 25. At the same time the drawer mechanism is released and ae bell crank lever moves in a clockwise direction releasing the tension on the spring 49 so that the switch C remains open, having opened a sufiicient time prior to the closing of the switch 0 to insure that no momentary operation of the alarm takes place. When the drawer is closed, counterclockwise movement of the bell crank lever insures opening of the switch 0 before sufiicient energy is stored up in spring 49 to snap switch C to the closed position against the holding action of the spring pressed ball.

Should the clerk in a store equipped with an apparatus of the present type be held up it is a simple matter to comply with the command of the hold-up man to open the cash drawer but this is done without making use of the key 12. This insures closing of the switch 0 without opening the switch C and an appropriate alarm is given which desirably is not audible in the store and the hold-up man may be apprehended as he leaves without being aware that notification has been given to others.

Obviously where burglar alarm circuits of the normally closed type are used such as are sometimes provided to insure the giving of an alarm upon intentional cutting of the wires by burglars, the switches O and C and their connections would be appropriately changed to properly function with this type of system. The mechanism shown is merely suggestive for obviously the switches could be arranged independently with suitable provision to prevent a momentary operation of the alarm if both happened to be closed at the same tim at the instant the drawer began to open. Any form of switch can be used for the purpose and it is not essential that the simple types illustrated be selected. Likewise, diiierent cash register mechanisms may be adapted for operation with the switches without departing from the basic features of the invention.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

1. In a cash register burglar alarm system, in combination, a cash register having a slidably mounted spring opened drawer, a plurality of keys for releasing said drawer, an electric switch biased to closed-circuit position, cooperating means on said switch and drawer to hold said switch in open-circuit position only when the drawer is fully closed, a second switch biased to closed-circuit position, means associating a selected one of said keys to open said second switch when pressed to drawer releasing position, a battery, an alarm and means connecting said switches, battery and alarm in series whereby the alarm is sounded if the drawer is opened without actuation of the selected key.

2. In a cash register burglar alarm system, in combination, a switch biased to closed-circuit position and constructed and arranged to be held open by the closed drawer oi the cash register, a second switch normally biased to closed circuit position and arranged to be opened by a selected key on the cash register and means to connect said switches in series and with an alarm and source of current for the purpose described.

3. In a cash register burglar alarm system, in combination, a switch, means biasing said switch to closed-circuit position, said switch being arranged to be held open by the closed drawer oi the cash register, a second switch means normally biasing the switch to closed-circuit position, said switch being arranged to be opened by a selected key on the cash register, means to connect said switches in series and with an alarm and source of current for the purpose described and means to maintain second switch in open-circuit position while the first switch is in closed-circuit position.

4. In a cash register burglar alarm system, in combination, a switch, means biasing said switch to closed circuit position, said switch being arranged to be held open by the closed drawer of the cash register, a second switch, means normally biasing the switch to closed-circuit position, said switch being arranged to be opened by a selected key on the cash register, means to connect said switches in series and with an alarm and source of current for the purpose described and means mechanically associating said switches whereby upon operation of the selected key the normally closed switch opens before the normally open switch closes.

5. In combination with a cash register having operating keys and a sliding drawer, spring actuated to open position when released by a properly selected, transaction indicating combination of keys, of a switch mechanism and alarm circuit controlled thereby, said switch mechanism being jointly associated with said drawer and a selected one of said keys, said mechanism normally maintaining an open-circuit when the drawer is closed or when opened by a combination including the selected key, said mechanism being constructed and arranged to close the alarm circuit when the drawer is opened by a key or keys not including the selected one.

6. In combination with a cash register having a sliding drawer spring actuated to open position and released by operating keys therefor, a switch comprising, a casing adapted to be mounted in the space behind said drawer, a switch in said casing biased toward closed position and having means engageable by the drawer when closed to hold it in open-circuit position, a second switch in said casing, means to bias said switch to closed-circuit position, means to associate said second switch with a selected one of said keys for movement to open-circuit position upon actuation of said key and means for connecting saidswitches in series and with an alarm and. source of current.

'7. In combination with a cash register having a sliding drawer spring actuated to open position and released by operating keys therefor, a switch comprising, a casing adapted to be mounted in the space behind said drawer, a switch in said casing biased toward closed position and having means engageable by the drawer when closed to hold it in open-circuit position, a second switch in said casing, means to bias said switch to closed-circuit position, means to associate said second switch with a selected one of said keys for movement to open-circuit position upon actuation of said key, means to hold said second switch in open-circuit position after release of said key and means for connecting said switches in series and with an alarm and source of current.

8. In combination for use with a cash register having a sliding drawer spring actuated to open position and released by operating keys therefor, a switch comprising, a casin adapted to be mounted in the space behind said drawer, a switch in said casing biased toward closed position and having means engageable by the drawer when closed to hold it in open-circuit position, a second switch in said casing, means to bias said switch to closed-circuit position, means to associate said second switch with a selected one of said keys for movement to open-circuit position upon actuation of said key, means to hold said second switch in open-circuit position after release of said key, means to return said second switch to closed-circuit position when the drawer is closed and means for connecting said switches in series and with an alarm and source of current.

9. In a cash register having a slidable drawer, in combination, an alarm circuit, a switch in said circuit, means biasing the switch to closed position, said switch being so constructed and arranged as to be normally held open by the drawer when closed, concealed switch means normally closed and connected in series with the first switch, and key means to open said switch means and the circuit.

A. DOROTHY M. STELTER. FRANCIS C. W. STELTER. 

